MySQL由HTML中的node.js生成，由react.js生成

Question

I make my first web application with nodes and reacc. I do sql query in node.js and show html elements in my page. I need help getting the result of sql in my html page as json date. I put some of the code with my experiments, which may be very wrong. Regards.

 var React = require('react'); var DefaultLayout = require('./layout/master'); var mysql = require('mysql'); var connection = mysql.createConnection({ port: '3301', host: 'localhost', user: 'root', password: 'root', database: 'nodedb', }); connection.connect(); function getArticless() { connection.query('select * from articles', function(err, result) { if (err) JSON.stringify(err); else JSON.stringify(result); }); } const jsonArticles = getArticless(); var IndexComponent = React.createClass({ render: function() { return ( <DefaultLayout name={this.props.name}> <div> {jsonArticles } </div> </DefaultLayout> ) } }); module.exports = IndexComponent; 

Answer 1

I am not familiar with the nuances of server side rendering with react, however there is one glaring issue that stands out with your code. I do not know for sure if fixing this will make it all work, but it certainly wont work with this issue.

getArticles is a function that returns nothing and yet you call it as if it is a function that returns something. Now even if you would add a return statement to this function, it will still return undefined because calls to the database happen asynchronously. This means that the function will return before the data was actually retrieved from the db. This function would at the very least require a callback to be passed in, or else you can look in to the mysql-promise library and use that instead.